use bevy::feathers::{FeathersPlugins, containers::*, controls::*, dark_theme::create_dark_theme, display::*, theme::UiTheme};
use bevy::ui_widgets::{Activate};
use bevy::prelude::*;

use crate::grid::{Grid, GridElement};
use crate::simulation::SimulationStatus;
use crate::view::editor::EditorTools;

pub struct UIPlugin;

impl Plugin for UIPlugin {
    fn build(&self, app: &mut App) {
        app.add_plugins(FeathersPlugins)
            .insert_resource(UiTheme(create_dark_theme()))
            .add_systems(Startup, ui.spawn())
            .add_systems(Update, count_water_amount);
    }
}

#[derive(Component, Clone, Default)]
struct WaterLabel;

#[derive(Component, Clone, Default)]
struct SpeedLabel;

#[derive(Component, Clone, Default)]
struct ToolLabel;

const MAX_FREQUENCY: u32 = 512;
const MIN_FREQUENCY: u32 = 1;

fn count_water_amount(grid: Res<Grid>, text: Single<&mut Text, With<WaterLabel>>) {
    let mut sum: u32 = 0;
    for i in 0..grid.cell_amount() {
        let GridElement::Water { amount: water_amount } = grid.data[i as usize] else {
            continue;
        };

        sum += water_amount;
    }

    let mut label = text.into_inner();
    label.0 = format!("Water amount: {} liters",sum);
}

fn ui() -> impl Scene {
    bsn! {
        Node {
            width: percent(100),
            height: percent(100),
            align_items: AlignItems::Start,
            justify_content: JustifyContent::Start,
            display: Display::Flex,
            flex_direction: FlexDirection::Row,
            column_gap: px(8)
        }
        Children [
            debug_column()
            editor_column()
        ]
    }
}

fn debug_column() -> impl Scene {
    bsn! {
        Node {
            display: Display::Flex,
            flex_direction: FlexDirection::Column,
            align_items: AlignItems::Stretch,
            justify_content: JustifyContent::Start,
            padding: px(8),
            row_gap: px(8),
            width: px(256),
            min_width: px(256),
        }
        pane()
        pane_header()
        pane_body()
        Children [
            water_amount_label(),
            pause_button(),
            simulation_speed(),
        ]
    }
}

fn editor_column() -> impl Scene {
    bsn! {
        Node {
            display: Display::Flex,
            flex_direction: FlexDirection::Column,
            align_items: AlignItems::Stretch,
            justify_content: JustifyContent::Start,
            padding: px(8),
            row_gap: px(8),
            width: px(256),
            min_width: px(256),
        }
        pane()
        pane_header()
        pane_body()
        Children [
            label("Tools")
            ToolLabel,
            @FeathersButton {
                @caption: bsn!{label("None")}
            }
            on(|_activate: On<Activate>, mut tool: ResMut<EditorTools>, mut label: Single<&mut Text, With<ToolLabel>>| {
                *tool = EditorTools::None;
                label.0 = "Current tool: None".to_string();
            }),
            @FeathersButton {
                @caption: bsn!{label("Paint")}
            }
            on(|_activate: On<Activate>, mut tool: ResMut<EditorTools>, mut label: Single<&mut Text, With<ToolLabel>>| {
                *tool = EditorTools::Paint { position: UVec3::default(), block: GridElement::Solid };
                label.0 = "Current tool: Paint".to_string();
            }),
        ]
    }
}

fn water_amount_label() -> impl Scene {
    bsn! {
        Node {
            width: percent(100),
            height: px(32),
            
        }
        Children [
            label("")
            WaterLabel
        ]
    }
}

fn pause_button() -> impl Scene {
    bsn!{
        @FeathersButton {
            @caption: bsn! { label("Toggle simulation") }
        }
        on(|_activate: On<Activate>, current_state: Res<State<SimulationStatus>>, mut next_state: ResMut<NextState<SimulationStatus>>|  {
            next_state.set(match current_state.get() {
                SimulationStatus::Paused => SimulationStatus::Continued,
                SimulationStatus::Continued => SimulationStatus::Paused,
            });
        })
    }
}

fn simulation_speed() -> impl Scene {
    bsn! {
        Node {
            display: Display::Flex,
            align_items: AlignItems::Stretch,
            justify_content: JustifyContent::Start,
            width: percent(100),
            height: px(32),
        }
        Children [
            @FeathersButton {
                @caption: bsn! { label("<<") }
            }
            on(|_activate: On<Activate>, mut time: ResMut<Time<Fixed>>, mut label: Single<&mut Text, With<SpeedLabel>>|{
                let mut current_frequency = (1./time.timestep().as_secs_f64()) as u32;
                current_frequency = if current_frequency <= MIN_FREQUENCY {MIN_FREQUENCY} else {current_frequency / 2};
                time.set_timestep_hz(current_frequency as f64);
                label.0 = format!("{} hz", current_frequency);
            })
            ,
            label("")
            SpeedLabel
            Node {
                justify_self: JustifySelf::Stretch
            },
            @FeathersButton {
                @caption: bsn! { label(">>") }
            }
            on(|_activate: On<Activate>, mut time: ResMut<Time<Fixed>>, mut label: Single<&mut Text, With<SpeedLabel>>|{
                let mut current_frequency = (1./time.timestep().as_secs_f64()) as u32;
                current_frequency = if current_frequency >= MAX_FREQUENCY {MAX_FREQUENCY} else {current_frequency * 2};
                time.set_timestep_hz(current_frequency as f64);
                label.0 = format!("{} hz", current_frequency);
            }),
        ]
    }
}